To investigate the effect of temperature on the adsorption performance of Cd²⁺ and Pb²⁺ in semi coke shale, four types of semi tar shale (OS-200, OS-400, OS-600, OS-800) were prepared by modifying the semi coke with oil shale (OS) residue from the Balikun mining area in Xinjiang at 200 ~ 800 ℃. The phase characterization was carried out using techniques such as scanning electron microscope(SEM), transmission electron microscope(TEM), thermogravimetric analysis (TGA), X-ray diffraction(XRD), Brunauer-Emmett-Teller(BET), and Fourier transform infrared spectroscopy (FTIR). The adsorption performance of Cd²⁺ and Pb²⁺ was studied through adsorption experiments. The results show that through coking at different temperatures, the physical and thermogravimetric properties of OS underwent significant changes. On the basis of not changing its basic mineral composition, the activity of —OH, C ＝ O, and Si—O—Si chemical bonds is changed, and its specific surface area is increased. OS-600 exhibits better adsorption performance, and the Langmuir equation and quasi second order kinetic model can better fit the adsorption process at pH = 7 and 25 ℃. The fitting results show that the theoretical maximum adsorption capacity of OS-600 for Cd²⁺ is 9.04 mg/g, and the maximum adsorption capacity for Pb²⁺ is 44.84 mg/g. The measured adsorption capacities of OS-600 for Cd²⁺ and Pb²⁺ are 6.69 mg/g and 35.42 mg/g, respectively, which are 53.44% and 71.69% higher than the original adsorption capacity of OS. The optimal semi coke temperature for OS is 400 ~ 700 ℃, and the semi coke time should not be less than 2 hours. The research results provide theoretical support for optimizing the temperature conditions when preparing adsorbent materials using semi coke OS.